1. Field
The present invention relates generally to vacuum packaging machines used to seal contents in a vacuum bag. More specifically, embodiments of the present invention concern a vacuum packaging machine configured for use in a chamber packaging operation, where the bag and the contents to be sealed therein are entirely received within the vacuum chamber of the machine, or an external packaging operation, where only part of the bag is received within the vacuum chamber.
2. Discussion of Prior Art
Vacuum packaging machines have long been used to seal contents in vacuum bags made of synthetic resin material. While such machines are typically used to seal foodstuffs for storage and later consumption, other items can be vacuum packaged as well. In general, prior art machines seal contents within a vacuum bag by evacuating air from the bag to achieve a vacuum condition while retaining substantially all of the contents within the bag. While maintaining the vacuum condition, the machine then seals the contents within the bag by activating a heated sealing mechanism. The mechanism melts the panels of the bag to one another along a seal line to seal the open margin closed.
One prior art machine for conventional vacuum packaging is an external packaging system where only part of the bag (i.e., the open margin) is positioned within the vacuum chamber, while the remainder of the bag and the contents being sealed are outside of the vacuum chamber. Another prior art machine for conventional vacuum packaging is a chamber packaging system where the vacuum bag and the contents being sealed are positioned entirely within the vacuum chamber.
However, the prior art vacuum packaging machines have various deficiencies. For instance, conventional external packaging systems draw any liquid contents within the bag toward the open margin during air evacuation. This can lead to liquid migrating out of the bag and onto surfaces within the vacuum chamber. The liquid can also move to a location along the seal line such that the liquid interferes with proper sealing of the vacuum bag. Prior art chamber packaging systems are deficient because the size of the vacuum chamber limits the size of the contents to be sealed in the vacuum bag.